#include <stdio.h>

int main() {
    int n;
    scanf("%d", &n);
    int arr[n];
    int i = 0;
    for (i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }
    int sum = 0;
    int i = 0;
    float a = 0.0f;
    while (i < n) {
        sum += arr[i];
        i++;
    }
    a = (float)sum / n;
    printf("%.2f", a);
    return 0;
}
